Fair Value Measurement - Additional Information (Detail) (USD $)	12 Months Ended			1 Months Ended	9 Months Ended
	Dec. 31, 2014	Dec. 31, 2013 security	Dec. 31, 2012	Jan. 31, 2014 right store	Sep. 30, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Proceeds from dispositions of businesses and contracts	$ 16,525,000	$ 2,163,000	$ 1,999,000
Held-to-maturity securities, amortized cost	68,700,000
Held-to-maturity securities, sold security, realized gain (loss)	95,000
Number of securities in unrealized loss position		18
Number of securities		48
Fixed Rate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long term debt, carrying value	400,000,000	125,000,000
RIMCO
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of stores sold during period				27
Number of franchise rights sold during period				5
Proceeds from dispositions of businesses and contracts				10,000,000
Asset impairment charges		766,000
Gain (loss) on disposition of business					$ 762,000